The present invention relates generally to optoelectronic assemblies having optical components and methods for making the same; more particularly, the present invention relates to an assembly having optical components mounted on a quasi-planar substrate and a flexure and methods for making the same.
Sealed packages are necessary to contain, protect, couple to optical fibers and electrically connect optoelectronic components. Optoelectronics packaging is one of the most difficult and costly operations in optoelectronics manufacturing. Optoelectronic packages provide submicron alignment between optical elements, high-speed electrical connections, excellent heat dissipation, and high reliability. Providing such features has resulted in optoelectronic packages that are larger, costlier and more difficult to manufacture than electronic packages. In addition, current designs of optoelectronic packages and associated fabrication processes are ill adapted for automation because today""s high-performance butterfly packages are characterized by a large multiplicity of mechanical parts (submounts, brackets, ferrules, etc.), three-dimensional (3D) alignment requirements, and poor mechanical accessibility.
U.S. Pat. No. 4,953,006 by Kovatz discloses a package for an edge-coupled optoelectronic device. The package includes a cover with a window, so that optoelectronic device, such as, for example, a laser, may be coupled to external optics, such as a lens or an optical fiber. Although this package provides hermeticity and high-speed electrical connections, it does not provide for a way to mount and align collimation or coupling optics nor optical fibers.
U.S. Pat. No. 5,005,178 by Kluitmans and Tjassens and U.S. Pat. No. 5,227,646 by Shigeno also disclose packages for optical and optoelectronic components. Kluitmans et al. discuss a package for a laser diode coupled to an optical fiber. The package includes a conducting rod so that the laser may be used at high speed. Shigeno describes a heat sink for cooling an enclosed laser diode, where the laser diode is preferably coupled to an optical fiber. However, in both of the above patents, it is difficult to align the laser diode with the optical fiber when constructing the package. Both designs use numerous parts in complex three dimensional arrangements and are unsuitable for automated assembly. U.S. Pat. No. 5,628,196 by Farmer discloses a package including a heat sink for a semiconductor laser, but provides no efficient means for coupling the laser to other optics.
The difficulty in alignment is made more problematic where welding is involved in the manufacturing of a package. The result of the welding process causes a shift to occur in the structure being welded. Therefore, even though something is aligned prior to welding, the result of the welding process may cause such shifts to occur. Where micron accuracy is needed, these shifts affect the over all yield. There are no preferred techniques to reduce the shifts.
Embodiments of the present invention overcome the limitations in the prior art.
An optoelectronic package is described. In one embodiment, the optoelectronic package includes a substrate having a floor, a first optical element coupled to the substrate, a second optical element, and a flexure coupled to the second optical element and the substrate to optically align the second optical with the first optical element. In one embodiment, the flexure has multiple legs coupled to a body using spring regions, wherein the body of the flexure includes two portions joining at an area of the body having a substantially reduced width with respect to the two portions.